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Full-Text Articles in Aerospace Engineering

A Technology Survey Of Emergency Recovery And Flight Termination Systems For Uas, Richard Stansbury, Wesley Tanis, Timothy Wilson May 2019

A Technology Survey Of Emergency Recovery And Flight Termination Systems For Uas, Richard Stansbury, Wesley Tanis, Timothy Wilson

Richard Stansbury

For safe flight in the National Airspace System (NAS), either under the current interim rules or under anticipated longer-term regulatory guidelines facilitating unmanned aircraft system (UAS) access to the NAS, the UAS must incorporate technologies and flight procedures to ensure that neither people nor property in the air, on the ground, or on or in the water are endangered by the failure of an onboard component, by inappropriate unmanned aircraft (UA) response to pilot commands, or by inadvertent entry by the UA into prohibited airspace. The aircraft must be equipped with emergency recovery (ER) procedures and technologies that ensure that …


The Next Step Beyond Identifying Field Variability: Integrating Unmanned Aerial Systems Into The Farm Management Workflow, Kevin A. Adkins, Christen C. Bailey, Aspen E. Taylor Apr 2018

The Next Step Beyond Identifying Field Variability: Integrating Unmanned Aerial Systems Into The Farm Management Workflow, Kevin A. Adkins, Christen C. Bailey, Aspen E. Taylor

Kevin A. Adkins, PhD

Precision agriculture strives to manage variations in the field in order to increase yield while adapting input factors to preserve resources and decrease production costs. Unmanned aerial systems (UAS) are advancing precision agriculture by allowing for nondestructive and convenient, as well as cost and time efficient mapping of spatial variation in fields with higher spatial resolution than previous methods. However, while there is much anticipation regarding the potential role for UAS in precision agriculture, their role still requires additional application-based testing. The objective of this work was to explore how growers best integrate the UAS product into their farm workflow. …


The Next Step Beyond Identifying Field Variability: On-Farm Investigations Using An Unmanned Aerial System To Accurately Diagnose Crop Disease, Kevin A. Adkins Apr 2018

The Next Step Beyond Identifying Field Variability: On-Farm Investigations Using An Unmanned Aerial System To Accurately Diagnose Crop Disease, Kevin A. Adkins

Kevin A. Adkins, PhD

Precision agriculture strives to manage variations in the field in order to increase yield while adapting input factors to preserve resources and decrease production costs. Unmanned aerial systems (UAS) are advancing precision agriculture by allowing for nondestructive and convenient, as well as cost and time efficient mapping of spatial variation in fields with higher spatial resolution than previous methods. However, while there is much anticipation regarding the potential role for UAS in precision agriculture, their role still requires additional application-based testing. The objective of this work was to explore how growers best integrate the UAS product into their farm workflow. …


Integrating Spaceshiptwo Into The National Airspace System, Erik Seedhouse, Pedro Llanos Aug 2017

Integrating Spaceshiptwo Into The National Airspace System, Erik Seedhouse, Pedro Llanos

Pedro J. Llanos (www.AstronauticsLlanos.com)

The increasing number of commercial suborbital space flights over the next decade may lead to the development of commercial suborbital transportation. This may lead to risks to civil aviation and the hazards that may arise from the interaction of suborbital spacecraft with controlled air space. To do this the National Airspace System will need to accommodate a growing number of suborbital spacecraft. An example of one of the suborbital vehicles being developed is Virgin Galactic’s SpaceShipTwo. This paper analyzes the performance of SpaceShipTwo using simulated nominal flight research data conducted at Embry-Riddle Aeronautical University’s Suborbital Spaceflight Simulator.


Comment On Faa Rule Revision - Transport Category Aircraft, Paul F. Eschenfelder, Valter Battistoni Nov 2015

Comment On Faa Rule Revision - Transport Category Aircraft, Paul F. Eschenfelder, Valter Battistoni

Paul F. Eschenfelder

No abstract provided.


Unlocking The Mysteries Of Flight: From The Top Down, Juan Merkt Jul 2015

Unlocking The Mysteries Of Flight: From The Top Down, Juan Merkt

Juan R. Merkt

Traditionally, principles of flight are taught from the bottom-up. That is, we start by examining underlying causes (properties of air) and later move up to top consequences (aircraft performance). This traditional approach is analogous to that used by airplane designers and is most obvious in theory of flight textbooks for pilots. The problem with a bottom-up approach is that it introduces basic concepts as isolated “parts” without providing a “big picture” context. This can lead to poor understanding among student pilots. I suggest an opposite approach. Rather than starting with the underlying causes of flight, we can unravel basic principles …


Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, Johann M. Schumann, Kristin Y. Rozier, Thomas Reinbacher, Ole J. Mengshoel, Timmy Mbaya, Corey Ippolito Jun 2015

Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, Johann M. Schumann, Kristin Y. Rozier, Thomas Reinbacher, Ole J. Mengshoel, Timmy Mbaya, Corey Ippolito

Ole J Mengshoel

For unmanned aerial systems (UAS) to be successfully deployed and integrated within the national airspace, it is imperative that they possess the capability to effectively complete their missions without compromising the safety of other aircraft, as well as persons and property on the ground. This necessity creates a natural requirement for UAS that can respond to uncertain environmental conditions and emergent failures in real-time, with robustness and resilience close enough to those of manned systems. We introduce a system that meets this requirement with the design of a real-time onboard system health management (SHM) capability to continuously monitor sensors, software, …


Autonomous Navigation And Control Of Unmanned Aerial Systems In The National Airspace, Michael Hlas, Jeremy Straub, Eunjin Kim Apr 2015

Autonomous Navigation And Control Of Unmanned Aerial Systems In The National Airspace, Michael Hlas, Jeremy Straub, Eunjin Kim

Jeremy Straub

Pilotless aircraft known as Unmanned Aerial Vehicles (UAVs) have been used extensively for military and intelligence purposes. This includes situations where the mission area is too dangerous for a pilot to fly, the length of the mission is longer than a pilot could stay awake or aircraft are used as cruise missiles that crash into their target. With the decreasing cost and miniaturization of computers, it has become possible to build UAVs that are small and inexpensive making them accessible to businesses, law enforcement, hobbyists and the general public.


The Use Of Low-Cost ‘Balloonsats’ For Stem Education With 3d Printing, Jeremy Straub, Josh Berk, John Nordlie, Ronald Marsh Apr 2015

The Use Of Low-Cost ‘Balloonsats’ For Stem Education With 3d Printing, Jeremy Straub, Josh Berk, John Nordlie, Ronald Marsh

Jeremy Straub

A new technology, known as 3D printing, allows the rap-id fabrication of plastic structures of virtually any config-uration. These structures are light-weight, dura-ble and inexpensive. This paper considers the utility of utilizing 3D printing to create enclosures for ‘BalloonSats’ – small, low-cost spacecraft analog which can be utilized by students to understand space engi-neering, conduct near-space science (e.g., physics, bio-logical and other experiments) and touch the edge of space.


Update On The Progress Of The 1-U Open Cubesat Development, Jeremy Straub, Ronald Marsh Apr 2015

Update On The Progress Of The 1-U Open Cubesat Development, Jeremy Straub, Ronald Marsh

Jeremy Straub

The OpenOrbiter program [1] is developing a low-cost framework for the creation of space-craft [2] by researchers and educators world-wide [3]. In line with the objective of enabling future educational use by others, educational assessment [4, 5] has been a key focus. Sever-al areas were assessed: students were asked what types of benefits they sought from their participation [6], assessment of benefit attain-ment is ongoing. Work on the development of a designs (See Figures 2 and 8) that can be used to build a spacecraft with a cost of under $5,000 [7] using primarily COTS parts and testing (see Figure …


The Differences Are Not So Great: High Altitude Balloon And Small Spacecraft Software Development, Jeremy Straub, Ronald Marsh Jun 2014

The Differences Are Not So Great: High Altitude Balloon And Small Spacecraft Software Development, Jeremy Straub, Ronald Marsh

Jeremy Straub

Previous work discussed critical differences in planning, developing hardware for and executing a high altitude balloon (HAB) mission. One area where this difference is less pronounced is in software development, allowing HABs to be utilized as a ‘software testbed’ for many orbital missions. This paper provides an overview of the software development process for both orbital and HAB craft, highlighting differences between the two processes and the numerous similarities. It concludes by presenting a framework for analyzing the suitability of HAB testing for small satellite software.


A Low-Cost Gps/Inertial Position Determination System For High Altitude Balloons, Spacecraft And Unmanned Aerial Systems, Tyler Leben, Jeremy Straub, Ronald Marsh Mar 2014

A Low-Cost Gps/Inertial Position Determination System For High Altitude Balloons, Spacecraft And Unmanned Aerial Systems, Tyler Leben, Jeremy Straub, Ronald Marsh

Jeremy Straub

A low-cost system is needed to determine precise position and predict future location in flight and low-Earth orbit. One method to accomplish this task is to utilize an onboard GPS receiver. GPS units receive data from the GPS NAVSTAR constellation of 24 satellites in the form of a 37 byte ASCII text sent at 4800 baud called NMEA sentences. The standard is 1 HZ, which is one sentence per second, but can be more. Ideally, from this data a PVT (position, velocity, time) and altitude can be determined. This data is then transferred from the GPS module to a separate …


The Path To Regulation Of Small Unmanned Aerial Vehicles In The United States, Jeremy Straub, Joe Vacek Mar 2014

The Path To Regulation Of Small Unmanned Aerial Vehicles In The United States, Jeremy Straub, Joe Vacek

Jeremy Straub

This poster presents an overview of proposed regulations that are presented in [1] related to a re-vised approach to small Unmanned Aerial Vehicles (UAV) regulation in the United States. Prospective strategies for enhancing UAV regulation are consid-ered as is the pathway to develop and implement these regulations. The benefits of changing the UAV regulatory regime are discussed, on both a user/prospective user and societal scale.


The Use Of Solar Balloons At Und As A Low-Cost Alternative To Helium Balloons For Small Spacecraft Testing And Stem Education, John Nordlie, Jeremy Straub, Chris Theisen, Ronald Marsh Mar 2014

The Use Of Solar Balloons At Und As A Low-Cost Alternative To Helium Balloons For Small Spacecraft Testing And Stem Education, John Nordlie, Jeremy Straub, Chris Theisen, Ronald Marsh

Jeremy Straub

Helium-filled latex weather balloons have been utilized for many years to carry small satellite prototypes and subsystems into the stratosphere to allow testing in a “near space” (stratospheric) environment. A variety of environmental factors similar to the space environment can be found in this region, such as a rarified atmosphere, increased thermal stress including very low temperatures, increased solar radiation, the necessity of remote command and control, tracking, and telemetering of data. While this method of flight testing has been well-proven, a recent increase in the price of helium has driven the cost of such test programs to much higher …


The Use Of 3d Printing To Enable High Altitude Balloon Missions, Jeremy Straub Mar 2014

The Use Of 3d Printing To Enable High Altitude Balloon Missions, Jeremy Straub

Jeremy Straub

The 3D printing technology allows the low-cost creation of structures based on user-defined configuration parameters. Unlike other plastic-forming technologies, there is no tooling cost related to the creation of a mold. Because of this, highly-customized structures can be created with a minimum production quantity of one, allowing adaptation to individual mission needs (for a single-HAB mission) or the change of the structure across a multi-unit run (e.g., to test various configurations or as part of a study requiring multiple payloads with different configurations).

This paper considers the mission possibilities enabled by the use of 3D printing for HAB structures. These …


Investigation Of An Autonomous Landing Sensor For Unmanned Aerial Systems, A Ram (Bella) Kim Jan 2014

Investigation Of An Autonomous Landing Sensor For Unmanned Aerial Systems, A Ram (Bella) Kim

A Ram (Bella) Kim

This research focused on characterizing the precision, reliability, sensitivity, and uncertainty of an autonomous landing sensor. Currently, the most dangerous flight phase for autonomous aircraft is the landing and takeoff segments, accounting for almost 70% of crashes. This research analyzes the effects of the color and roughness of the landing surface, fog, ice, and varying aircraft angles on the performance of an automated landing sensor. An investigation of suitable sensors was performed and the Dimetix FLS-C30 laser altimeter was selected for testing. The standard deviation and uncertainty of each condition was found and compared. It was determined that surface color, …


Verification Of Video Frame Latency Telemetry For Uav Systems Using A Secondary Optical Method, Sam B. Siewert Jan 2014

Verification Of Video Frame Latency Telemetry For Uav Systems Using A Secondary Optical Method, Sam B. Siewert

Sam B. Siewert

This paper presents preliminary work and a prototype computer vision optical method for latency measurement for an UAS (Uninhabited Aerial System) digital video capture, encode, transport, decode, and presentation subsystem. Challenges in this type of latency measurement include a no-touch policy for the camera and encoder as well as the decoder and player because the methods developed must not interfere with the system under test. The goal is to measure the true latency of displayed frames compared to observed scenes (and targets in those scenes) and provide an indication of latency to operators that can be verified and compared to …


Solar Ballooning: A Low-Cost Alternative To Helium Balloons For Small Spacecraft Testing, John Nordlie, Jeremy Straub, Chris Theisen, Ronald Marsh Jan 2014

Solar Ballooning: A Low-Cost Alternative To Helium Balloons For Small Spacecraft Testing, John Nordlie, Jeremy Straub, Chris Theisen, Ronald Marsh

Jeremy Straub

Helium-filled latex weather balloons have been utilized to carry small satellite prototypes and subsystems into the stratosphere to allow testing in a “near space” environment. This provides a variety of environmental factors similar to the space environment, such as a rarified atmosphere, increased thermal stress, increased solar radiation, the necessity of remote command and control, tracking, and telemetering of data. While this method of flight testing has been well-proven, a recent spike in the price of helium has driven the cost of such test programs to much higher levels. In this poster, an alternative technology to provide the flight mechanism, …


Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, Johann Schumann, Kristin Y. Rozier, Thomas Reinbacher, Ole J. Mengshoel, Timmy Mbaya, Corey Ippolito Sep 2013

Towards Real-Time, On-Board, Hardware-Supported Sensor And Software Health Management For Unmanned Aerial Systems, Johann Schumann, Kristin Y. Rozier, Thomas Reinbacher, Ole J. Mengshoel, Timmy Mbaya, Corey Ippolito

Ole J Mengshoel

Unmanned aerial systems (UASs) can only be deployed if they can effectively complete their missions and respond to failures and uncertain environmental conditions while maintaining safety with respect to other aircraft as well as humans and property on the ground. In this paper, we design a real-time, on-board system health management (SHM) capability to continuously monitor sensors, software, and hardware components for detection and diagnosis of failures and violations of safety or performance rules during the flight of a UAS. Our approach to SHM is three-pronged, providing: (1) real-time monitoring of sensor and/or software signals; (2) signal analysis, preprocessing, and …


Enabling Interplanetary Small Spacecraft Science Missions With Model Based Data Analysis, Jeremy Straub Jun 2013

Enabling Interplanetary Small Spacecraft Science Missions With Model Based Data Analysis, Jeremy Straub

Jeremy Straub

Small spacecraft operating outside of Earth orbit are significantly constrained by the communica- tions link available to them. This is particularly true for stand-alone craft that must rely on their own antenna and transmission systems (for which gain and available power generation are limited by form factor); it is also applicable to ‘hitchhiker’-style missions which may be able to utilize (quite likely very limited amounts of) time on the primary spacecraft’s communications equip- ment for long-haul transmission.

This poster presents the adaptation of the Model-Based Transmission Reduction (MBTR) frame- work’s Model-Based Data Analysis (MBDA) component for use on an interplanetary …


Operating Standards For The High Altitude Ballooning Community, Jeremy Straub, John Nordlie, Ernest Anderson Jun 2013

Operating Standards For The High Altitude Ballooning Community, Jeremy Straub, John Nordlie, Ernest Anderson

Jeremy Straub

This paper provides an overview of work to define a set of standards for adoption by the academic high altitude balloon community. These standards go above-and-beyond the requirements imposed by §101 of the Federal Aviation Regulations, incorporating best practices and suggesting how §101 requirements should be interpreted and applied in several situations.

One area where FAR§101 is extremely vague is with regards to the operations of balloons with small payloads. These payloads are exempt from most requirements; however, they are required to not create a “hazard”. Problematically, what exactly qualifies as a “hazard” is not defined in FAR§101 or elsewhere …


Creating Low-Cost ‘Balloonsats’ For Stem Education With 3d Printing, Jeremy Straub May 2013

Creating Low-Cost ‘Balloonsats’ For Stem Education With 3d Printing, Jeremy Straub

Jeremy Straub

A new technology, known as 3D printing, allows the rapid fabrication of plastic structures of virtually any configuration. These structures are light-weight, durable and inexpensive. This paper considers the utility of utilizing 3D printing to create enclosures for ‘BalloonSats’ – small, low-cost spacecraft analog which can be utilized by students to understand space engineering, conduct near-space science (e.g., physics, biological and other experiments) and touch the edge of space.

The utility of 3D printed structures for use in the near-space low-temperature and low-pressure environment is considered. This analysis falls into four key areas. First, the ability of the structures to …


Desktop Warfare: Robotic Collaboration For Persistent Surveillance, Situational Awareness And Combat Operations, Jeremy Straub May 2013

Desktop Warfare: Robotic Collaboration For Persistent Surveillance, Situational Awareness And Combat Operations, Jeremy Straub

Jeremy Straub

Robotic sensing and weapons platforms can be controlled from a desktop workstation on the other side of the planet from where combat is occurring. This minimizes the potential for injury to soldiers and increases operational productivity. Significant work has been undertaken and is ongoing related to the autonomous control of battlefield sensing and warfighting systems. While many aspects of these operations can be performed autonomously, in some cases it is necessary (due to technical limitations) or desirable (due to legal or political implications) to involve humans in the low-level decision making. This paper reviews a number of specific applications where …


A Human Proximity Operations System Test Case Validation Approach, Justin Huber, Jeremy Straub Mar 2013

A Human Proximity Operations System Test Case Validation Approach, Justin Huber, Jeremy Straub

Jeremy Straub

A Human Proximity Operations System (HPOS) poses numerous risks in a real world environment. These risks range from mundane tasks such as avoiding walls and fixed obstacles to the critical need to keep people and processes safe in the context of the HPOS’s situation-specific decision making. Validating the performance of an HPOS, which must operate in a real-world environment, is an ill posed problem due to the complexity that is introduced by erratic (non-computer) actors. In order to prove the HPOS’s usefulness, test cases must be generated to simulate possible actions of these actors, so the HPOS can be shown …


The North Dakota Space Robotics Program: Teaching Spacecraft Development Skills To Students Statewide With High Altitude Ballooning, Jeremy Straub, Ronald Fevig Jun 2012

The North Dakota Space Robotics Program: Teaching Spacecraft Development Skills To Students Statewide With High Altitude Ballooning, Jeremy Straub, Ronald Fevig

Jeremy Straub

The University of North Dakota is serving as the lead institution in a statewide effort to develop student spacecraft engineering skills. This effort, which is part of the North Dakota Space Robotics Program (NDSRP), provides students the ability to participate in the design, development and fabrication of a small satellite analog that is launched by a high altitude balloon. The first iteration of the NDSRP Near-Spacecraft Project is generating a functional prototype of a remote sensing payload, which will perform onboard image processing. This project included undergraduate and graduate students from two institutions and five different academic departments. The students …


Formalizing Mission Analysis And Design Techniques For High Altitude Ballooning, Jeremy Straub, Ronald Fevig Jun 2012

Formalizing Mission Analysis And Design Techniques For High Altitude Ballooning, Jeremy Straub, Ronald Fevig

Jeremy Straub

High altitude balloon (HAB) missions can be and are used to teach concepts related to spacecraft and satellite design. A HAB mission, however, presents unique characteristics, which must be understood and respected to produce a desirable outcome. Because of this, flying an unaltered satellite design as a HAB payload would be as undesirable as utilizing an unaltered HAB design as a satellite. A well-defined process for HAB mission design is thus needed. The process presented mirrors commonly used space mission design processes to facilitate easy transition between the two. It is also comparatively simple, due to the smaller scale of …


A Perching Landing Gear For A Quadcopter, Elsa Culler, Gray Thomas, Christopher Lee Apr 2012

A Perching Landing Gear For A Quadcopter, Elsa Culler, Gray Thomas, Christopher Lee

Christopher Lee

The design, fabrication, and testing of two prototypes of a landing gear mechanism that would allow a quadcopter to grasp and perch upon a branch-like structure are presented. The prototypes are based upon a snapping-claw mechanism that is triggered on the impact of landing. A complaint claw, fabricated using shape deposition manufacturing techniques, can conform to various shapes and contours of perching structures. Results from flight tests with a commercial off-the-shelf quadcopter and zip line tests are presented which demonstrate the performance of the mechanism.


Assessment Of Carbon-Phenolic-In-Air Chemistry Models For Atmospheric Reentry, Alexandre Martin, Iain D. Boyd Jun 2010

Assessment Of Carbon-Phenolic-In-Air Chemistry Models For Atmospheric Reentry, Alexandre Martin, Iain D. Boyd

Alexandre Martin

Recent and future re-entry vehicle designs use ablative material as the main component of the heat shield of their thermal protection system. In order to properly predict the behavior of the vehicle, it is imperative to take into account the gases produced by the ablation process when modeling the reacting flow environment. In the case of charring ablators, where an inner resin is pyrolyzed at a relatively low temperature, the composition of the gas expelled in the boundary layer is complex and might lead to thermal chemical reactions that cannot be captured with simple flow chemistry models. In order to …


Mesh Tailoring For Strongly Coupled Computation Of Ablative Material In Nonequilibrium Hypersonic Flow, Alexandre Martin, Iain D. Boyd Jun 2010

Mesh Tailoring For Strongly Coupled Computation Of Ablative Material In Nonequilibrium Hypersonic Flow, Alexandre Martin, Iain D. Boyd

Alexandre Martin

A one-dimensional material response implicit solver with surface ablation and pyrolysis is strongly coupled to LeMANS, a CFD code for the simulation of weakly ionized hypersonic flows in thermo-chemical non-equilibrium. Using blowing wall boundary conditions and a moving mesh algorithm, the results of a strongly coupled solution of a sample re-entry problem are presented. Because of the requirement of a coupling scheme, an Arbitrary Lagrangian-Eulerian (ALE) approach is used to compute the flux, allowing the mesh to move as the surface ablates. However, as the shape of the vehicle changes, the shock location and geometry are also modified. Using the …


Flight Attendant/Pilot Communication, In A Post 9/11 Environment: Viewed From Both Sides Of The Fortress Door"., Lori Brown Dec 2009

Flight Attendant/Pilot Communication, In A Post 9/11 Environment: Viewed From Both Sides Of The Fortress Door"., Lori Brown

Lori J. Brown

Reports and a recent global survey (Brown, et al., 2010) reported that out of 271 pilots and flight attendants, 13% indicated a discrete wireless communication device would not enhance safety, 18% indicate a slight effect, 33% indicated a device may somewhat enhance safety, and 21% indicated the device would greatly enhance safety. ...